Lactation

Evidence Considered in Estimating the Average Requirement

As indicated earlier in the section on infants, human milk-fed infants consume on average 400 μg/day of vitamin A in the first 6 months of life. The carotenoid content of human milk has been summarized in Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids (IOM, 2000). Because the bioconversion of carotenoids in milk and in infants is not known, the contribution of carotenoids in human milk to meeting the vitamin A requirement of infants was not considered. To set an EAR during pregnancy, 400 μg RAE/day is added to the EAR for nonpregnant adolescent girls and women to assure adequate body stores of vitamin A.

Vitamin A EAR and RDA Summary, Lactation

EAR for Lactation

14–18 years

885 μg RAE/day of vitamin A

19–30 years

900 μg RAE/day of vitamin A

31–50 years

900 μg RAE/day of vitamin A

The RDA for vitamin A is set by using a CV of 20 percent based on the calculated half-life values for liver vitamin A (see “Adults Ages 19 Years and Older”). The RDA is defined as equal to the EAR plus twice the CV to cover the needs of 97 to 98 percent of individuals in the group (therefore, for vitamin A the RDA is 140 percent of the EAR). The calculated values for the RDAs have been rounded to the nearest 100 μg.

RDA for Lactation

14–18 years

1,200 μg RAE/day of vitamin A

19–30 years

1,300 μg RAE/day of vitamin A

31–50 years

1,300 μg RAE/day of vitamin A

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